Laser field manipulation and laser damage resistance property of nanotextures on fused silica optics

Abstract

Nanotextures, being composed of an array of nanostructures, can manipulate the effective refractive index on the interface between air and optical substrates. Various optical properties, such as antireflection, antifogging, self-cleaning, enhanced absorption, have been achieved by nanotextures. Nanotextures have been considered to have great potential in the high-power laser system because of the single-material configuration. Here, we show design and fabrication of nanotextures on fused silica with high laser-induced damage threshold (LIDT) at the wavelengths 355 nm and 532 nm. The manipulation of light field intensity by nanostructures has been studied. When the average period of nanostructures is less than the 1/3 wavelength, the light field intensity in nanostructures can be lower than that in air. This is the theoretical basis for the high LIDT of fused silica nanotextures. Finally, we study laser induced damage performance of nanotextures. The experimental results show that the LIDT of fused silica can be improved by nanotextures. The LIDT of fused silica substrate was improved form 15 J/cm2 to 22 J/cm2 at the wavelengths 532 nm. This work promotes an application of nanotextures in high power/energy laser area.